With Simple JSF FlowScope it becomes very easy to define your beans in a flow scope. There are already quit a few frameworks that are capable of defining a scope with a lifetime between the standard Request and Session lifetime. Myfaces Orchestra, Seam and Myfaces Trinidad are a few of them. Besides the additional scope, they define a lot of other functionality that can be very handfull. But sometimes you need just a simple way to keep a bean for a few screens and of course you don't wan't to use the session scope for this.
Limitations
The project aimed to make a simple 'framework' so things like multiple flows are not possible. Another limitation is that Spring is used to define a custom scope and thus that your JSF backing beans must be declared in the Spring context and not with the Managed Bean facility of JSF.